1. Field of the Invention
The invention relates to a method of producing a one-piece corrugated jacket pipe of thermoplastic comprising the steps of forming a thermoplastic tube; shaping the tube into a corrugated pipe, which is closed over its circumference and has an axis and a corrugated section formed by a first corrugated partial section and a second corrugated section, the partial sections being such that when radially overlapping each other, the first partial section lies radially outwards and engages with the radially inward second partial section; cutting the corrugated pipe parallel to the axis in a cutting plane for the corrugated partial sections to form; thermally deforming the corrugated pipe such that the two corrugated partial sections lie one above the other radially and lap over each other in a peripheral direction. The invention further relates to a method of inserting at least one electric line into such a corrugated jacket pipe.
2. Background Art
A method of the generic type is known from WO98/32 202. In this case, the corrugated jacket pipe is thermally formed in such a way that the first corrugated partial section rests radially outwards on, and engages with, the second corrugated partial section directly after the forming. Practice has shown that the engagement of the first and the second corrugated partial section does not take place with the required radial prestress. This may result in small gaps forming so that electric lines might get squeezed or damaged. Moreover, the corrugated jacket pipe may open when bent during installation for instance in a vehicle, and the electric lines disposed in it may come out. This too may lead to damages of the electric lines.
This also applies to the corrugated jacket pipe known from WO97/32 379.